Musings with a Marine Biologist on Whales

Being married to a marine biologist has opened worlds that weren’t known to me before. Among many other intriguing wonders of the ocean world he introduced me to Velella Velella, or as they are known in layman speak, “by the wind sailors”. These intriguing creatures, so I learned, have a small rigid sail that projects into the air and catches the wind and wherever Velella Velella are in the world, their sail always aligns with the direction of the wind. I learned about jellyfish and their place in the ecosystem, about seahorses and their interesting life style. Dolphin’s of course, how could they not, put a smile on my face, but, nothing, nothing could have prepared me for the giants of the ocean, the whale sharks, the fin back whales, the humpback whales I had the privilege to meet up close with him many times, and who ultimately inspired me to compose Dreaming of Whales.

Why is it important to protect whales?

We are finally beginning to understand their critical roles in the functioning of marine ecosystems. These charismatic and majestic marine animals inspire and thrill people around the globe, and have much of the modern world advocating for their protection. Such wondrous beings deserve our efforts to protect them for future generations, as they are considerable assets to the health of the world’s oceans and our connection to nature.

The rorqual whales include the biggest animals to have ever lived on earth. The humpback whale (Megaptera novaeangliae) is one of the larger species of rorqual whales, which are baleen whales that have the skin of the throat and ventral surface marked with deep longitudinal furrows or pleats that can expand to allow the whale to engulf large amounts of water when feeding.

Humpback whales are famous for their haunting songs. Although both males and females produce a variety of sounds to communicate (grunts, groans, snorts and barks), only males produce the loud, complex, and low frequency songs that last up to 20 minutes and may be continually repeated for many hours at a time. These sounds are produced by a larynx-like structure found in the throat (they have no vocal chords), and they do not need to exhale to produce sounds. 

Whales within each population sing the same song, which may differ from whales of other populations in different regions. These songs change slowly over the years, and are not repeated in following years, although in some cases they appear to spread between adjacent populations over the course of successive breeding seasons. The songs appear to be a cultural or learned behavior. The purpose of the songs is not clear, but since only males sing them it is thought that they may be used to  attract or encourage mating in females. The songs may also be a challenge to other males, or even serve an echolocation function.

Whale Song (Male Humpbacks)

Humpbacks are relatively easy to identify at sea because of several characteristic features. They have a distinctive dorsal hump just below the dorsal fin, a knobbly appearance on the head and fins, breach frequently, and their pectoral fins are proportionally the longest fins of any cetacean (up to one third of their body length). With the dark dorsal surface and white under surface of the long pectoral fins, as well as a knobbly appearance to the anterior fin edge, their presence is hard to miss. One large humpback was 19 m (62 ft) long and had pectoral fins each measuring 6 m (20 ft) long. Besides aiding their general   maneuverability, the large size of Humpback pectoral fins is thought to aid in body temperature control as they migrate from their cold, high latitude feeding areas to the warmer tropical waters where they mate and give birth. They often migrate  up to 25,000 km (16,000 mi) round trip each year, which is the longest migration journey of any mammal.  Although Humpbacks have a world wide distribution, their appears to be distinctive populations in the different world oceans.

Humpbacks feed primarily on small pelagic crustceans (krill) and small fish such as herring. They have a variety of feeding methods, including the bubble net technique, and can consume enormous quantities of water and organisms with each feeding gulp.

In the past, Humpbacks were a frequent target for the whaling industry, and they were almost hunted to the brink of extinction before a 1966 moratorium was enacted. Numbers have partially recovered to approximately 80,000 animals worldwide, however collisions with ships, ocean noise pollution, and entanglement in fishing gear continue to take a toll on the species, as well as on most other whales.

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